Why do racists have lower IQs than non-racists?

Studies going back over 50 years have repeatedly arrived at the same conclusion—racists have lower IQs than non-racists. The average intelligence quotient (IQ) of all members of the human race is 100 on the Stanford-Binet scale, as illustrated in the bell curves in the figure below. The average IQ of racists is up to 4 IQ points less than this (Montagu 1952 & 1988, Allport 1946, Frenkel-Brunswick and Sanford 1945). The reasons this is true are not entirely clear. Does racism attract the unintelligent or do the unintelligent default into racist mentalities? An exploration of this phenomenon can be most informative.

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